Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761103Ab2J2Wiz (ORCPT ); Mon, 29 Oct 2012 18:38:55 -0400 Received: from smtprelay-h22.telenor.se ([195.54.99.197]:36759 "EHLO smtprelay-h22.telenor.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761053Ab2J2Wix (ORCPT ); Mon, 29 Oct 2012 18:38:53 -0400 X-SENDER-IP: [85.230.29.114] X-LISTENER: [smtp.bredband.net] X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AhidAL4Ej1BV5h1yPGdsb2JhbABEilK3KgICgQgZAQEBATg0gh4BAQQBJxMcIwULCANGFA0YChoTHodWAwkKsjMNiVQUinqBHYEmgieBeWEDlB+BVIV5hTmHcw4 X-IronPort-AV: E=Sophos;i="4.80,675,1344204000"; d="scan'208";a="435650436" From: "Henrik Rydberg" Date: Mon, 29 Oct 2012 23:43:31 +0100 To: Benjamin Tissoires Cc: Dmitry Torokhov , Jiri Kosina , Stephane Chatty , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 10/11] HID: introduce Scan Time Message-ID: <20121029224331.GA15608@polaris.bitmath.org> References: <1351241067-9521-1-git-send-email-benjamin.tissoires@gmail.com> <1351241067-9521-11-git-send-email-benjamin.tissoires@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1351241067-9521-11-git-send-email-benjamin.tissoires@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4543 Lines: 121 Hi Benjamin, > Win 8 digitizer devices provides the actual scan time computed by the > hardware itself. The value is global to the frame and is not specific > to the multitouch protocol (though only touch, not pen, should use it > according to the specification). > > Signed-off-by: Benjamin Tissoires > --- > Documentation/input/event-codes.txt | 7 +++++++ > drivers/hid/hid-input.c | 4 ++++ > drivers/hid/hid-multitouch.c | 11 +++++++++-- > include/linux/hid.h | 1 + > include/linux/input.h | 1 + > 5 files changed, 22 insertions(+), 2 deletions(-) This is a nice feature, useful in many other contexts. As such, I think it should be defined in the context of the input subsystem, with a more specific definition added to the documentation. For instance, is 100us suitable? When should it start at zero, at BTN_TOUCH? Or should it perhaps wrap around on unsigned integer instead? Or display the difference from the last event? > diff --git a/Documentation/input/event-codes.txt b/Documentation/input/event-codes.txt > index 53305bd..8f8c908 100644 > --- a/Documentation/input/event-codes.txt > +++ b/Documentation/input/event-codes.txt > @@ -174,6 +174,13 @@ A few EV_ABS codes have special meanings: > the input device may be used freely in three dimensions, consider ABS_Z > instead. > > +* ABS_SCAN_TIME: > + - Used when the device provides a timestamp for each frame. The unit must be > + 100us, and may be reset when the device don't send any events for a > + period of time. The values increment at each frame and thus, it can roll > + back to 0 when reach logical_max. If the device does not provide this > + information, the driver must not provide it to the user space. > + > * ABS_MT_: > - Used to describe multitouch input events. Please see > multi-touch-protocol.txt for details. > diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c > index 16cc89a..5fe7bd3 100644 > --- a/drivers/hid/hid-input.c > +++ b/drivers/hid/hid-input.c > @@ -675,6 +675,10 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel > map_key_clear(BTN_STYLUS2); > break; > > + case 0x56: /* Scan Time */ > + map_abs(ABS_SCAN_TIME); > + break; > + Is it not enough to map it in the case below? Or you mean this is picked up by hid core? > default: goto unknown; > } > break; > diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c > index c0ab1c6..21a120b 100644 > --- a/drivers/hid/hid-multitouch.c > +++ b/drivers/hid/hid-multitouch.c > @@ -447,12 +447,19 @@ static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, > mt_store_field(usage, td, hi); > td->last_field_index = field->index; > return 1; > + case HID_DG_SCANTIME: > + hid_map_usage(hi, usage, bit, max, > + EV_ABS, ABS_SCAN_TIME); > + set_abs(hi->input, ABS_SCAN_TIME, field, 0); > + td->last_field_index = field->index; > + return 1; > case HID_DG_CONTACTCOUNT: > td->last_field_index = field->index; > return 1; > case HID_DG_CONTACTMAX: > - /* we don't set td->last_slot_field as contactcount and > - * contact max are global to the report */ > + /* we don't set td->last_slot_field as scan time, > + * contactcount and contact max are global to the > + * report */ > td->last_field_index = field->index; > return -1; > case HID_DG_TOUCH: > diff --git a/include/linux/hid.h b/include/linux/hid.h > index 6216529..99a6418 100644 > --- a/include/linux/hid.h > +++ b/include/linux/hid.h > @@ -279,6 +279,7 @@ struct hid_item { > #define HID_DG_DEVICEINDEX 0x000d0053 > #define HID_DG_CONTACTCOUNT 0x000d0054 > #define HID_DG_CONTACTMAX 0x000d0055 > +#define HID_DG_SCANTIME 0x000d0056 > > /* > * HID report types --- Ouch! HID spec says 1 2 3! > diff --git a/include/linux/input.h b/include/linux/input.h > index ba48743..73c3a96 100644 > --- a/include/linux/input.h > +++ b/include/linux/input.h > @@ -796,6 +796,7 @@ struct input_keymap_entry { > #define ABS_TILT_X 0x1a > #define ABS_TILT_Y 0x1b > #define ABS_TOOL_WIDTH 0x1c > +#define ABS_SCAN_TIME 0x1d > > #define ABS_VOLUME 0x20 > > -- > 1.7.11.7 > Thanks, Henrik -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/